as the quite suggests, the availability of this dense network of specialized suppliers has given high-technology firms in silicon valley some considerable advantages over firms elsewhere. key inputs are cheaper and more easily available because there are many firms competing to provide them , and firms can concentrate on what they do best , contracting out other aspects of their business. for example, some silicon valley firms that specialize in providing highly sophisticated computer chips for particular customers have chosen to become "fabless." that is , they do not have any factories in which chips can be fabricated. instead , they concentrate on designing the chips,then hire another firm actually to fabricate them.